[BUG][KOTLIN-SPRING] String schema constraints not applied to header parameter

Created by: VladCananau

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

Header parameters are not correctly annotated with schema constraints on the controller methods.

openapi-generator version

5.2.0

OpenAPI declaration file content or url

openapi: 3.0.0
info:
  title: Repro
  version: '1.0'
  contact:
    name: Vlad
    email: vlad@vlad.vlad
paths:
  '/getSome/{what}':
    parameters:
      - $ref: '#/components/parameters/repro'
      - $ref: '#/components/parameters/what'
    get:
      responses:
        '200':
          description: OK
components:
  parameters:
    repro:
      name: X-Repro
      in: header
      required: true
      schema:
        $ref: '#/components/schemas/Id'
    what:
      name: what
      in: path
      required: true
      schema:
        $ref: '#/components/schemas/Id'
  schemas:
    Id:
      type: string
      pattern: '^[0-9]+$'
      minLength: 1
      maxLength: 5

Expected

@RequestHeader(value="X-Repro", required=true) @Pattern(regexp="^[0-9]+$") @Size(min=1,max=5) xRepro: kotlin.String

Actual

@RequestHeader(value="X-Repro", required=true) xRepro: kotlin.String

Steps to reproduce

openapi-generator generate -i repro.yml -g kotlin-spring -o .